Please check your internet connection and try again.
# Diclofenac
## Overview
Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase (COX) enzymes, reducing prostaglandin synthesis. It is available in oral, topical, and injectable formulations.
## Primary Indications
* Pain associated with osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis.
* Mild to moderate pain, including dysmenorrhea.
* Migraine treatment (oral formulation).
## Adult Dosing
* **Oral (immediate-release):** 25 mg three to four times daily, or 50 mg two to three times daily. Maximum: 150 mg/day for osteoarthritis/rheumatoid arthritis, 200 mg/day for other pain.
* **Oral (delayed-release):** 75 mg twice daily. Maximum: 150 mg/day.
* **Oral (extended-release):** 100 mg once daily. Maximum: 100 mg/day.
* **Topical gel/patch:** Applied to affected area as directed by product labeling (e.g., 1% gel, 40 mg patch).
* **Injectable:** 75 mg intramuscularly every 12 hours if needed for moderate to severe pain.
## Pediatric Dosing
* **Oral (immediate-release):** Generally not recommended for children under 14 years for rheumatoid arthritis. Specific dosing for pain or other indications is not well-established or may vary by formulation. Consult product labeling or pediatric formularies.
## Dose Adjustments
* **Renal Impairment:** Use with caution. Dose reduction may be considered in severe impairment, but no specific guidelines exist.
* **Hepatic Impairment:** Use with caution. Dose reduction may be considered in mild to moderate impairment. Contraindicated in severe hepatic impairment.
## Contraindications
* Hypersensitivity to diclofenac, aspirin, or other NSAIDs.
* History of asthma, urticaria, or allergic-type reactions after taking aspirin or other NSAIDs.
* Perioperative pain in the setting of coronary artery bypass graft (CABG) surgery.
* Third trimester of pregnancy.
## Adverse Effects
* **Common:** Gastrointestinal upset (nausea, dyspepsia, abdominal pain), diarrhea, rash.
* **Serious:** Cardiovascular thrombotic events (MI, stroke), GI bleeding, perforation, ulceration, renal toxicity, hepatic toxicity, hypersensitivity reactions, Stevens-Johnson syndrome, toxic epidermal necrolysis.
## Key Drug Interactions
* **Anticoagulants (e.g., warfarin):** Increased risk of bleeding.
* **Corticosteroids:** Increased risk of GI ulceration and bleeding.
* **SSRIs/SNRIs:** Increased risk of GI bleeding.
* **Other NSAIDs/Aspirin:** Increased risk of GI toxicity and additive effects.
* **ACE inhibitors, ARBs, diuretics:** Reduced antihypertensive effect and increased risk of renal impairment.
* **Lithium, Methotrexate:** Increased serum concentrations and toxicity.
## Monitoring
* **Renal function:** Especially in patients with pre-existing renal disease, dehydration, or those taking concomitant nephrotoxic agents.
* **Hepatic function:** Regularly, especially in patients with liver disease.
* **Signs of GI bleeding:** Melena, hematemesis, abdominal pain.
* **Blood pressure:** NSAIDs can increase blood pressure.
* **Signs of cardiovascular events:** Chest pain, shortness of breath, weakness, slurring of speech.
## Clinical Pearls
* Use the lowest effective dose for the shortest duration necessary to minimize risks.
* Consider gastroprotective agents (e.g., PPIs) in patients at high risk for GI complications.
* Topical formulations may offer a lower risk of systemic adverse effects for localized pain.
* Avoid concomitant use with other NSAIDs.
* Caution in elderly patients due to increased risk of adverse events.
***
This information is intended for healthcare professionals. Always verify current prescribing information and consult official drug compendia for the most up-to-date and complete details.
